The present invention relates, in general, to electronics, and more particularly, to methods of forming semiconductor devices and structure.
In the past, the electronics industry utilized various techniques to implement distributed systems including distributed power systems and particularly power systems that used multiple power supply controllers. Typically, such multiple power supply controllers each utilized a separate oscillator for controlling each power supply. The power supply systems typically connected the power supply controllers together and synchronized all the oscillators to a frequency of the oscillator of one of the power supply controllers. Such power supply systems and power supply controllers are the subject of U.S. Pat. No. 5,142,217 by inventor Walter S. Gontowski Jr. issued on Aug. 25, 1992 and U.S. Pat. No. 5,684,684 by inventors Harris et al issued on Nov. 4, 1997.
One problem with such power supply controllers and power supply systems was jitter of the oscillator frequency. Typically, the power supply controllers synchronized the frequency of the internal oscillator to the oscillator in the power supply system that had the highest frequency. If the frequency differential between the oscillators was less than about ten (10) percent, the power supply controllers typically alternated between being the synchronizing controller and the synchronized controller. This alternating back-and-forth caused the oscillator frequency to jitter resulting in improper operation of the power supply regulator and power supply system. Additionally, the power supply controllers typically could only synchronize to the fastest frequency of the oscillators in the power supply system.
Accordingly, it is desirable to have a power supply controller that can synchronize to frequencies that are higher and lower than the controller""s oscillator frequency, that does not have jitter in the oscillator frequency, and that does not alternate between being the synchronized and synchronizing frequency.